charon.plugins.socket-default.fwmark = Firewall mark to set on outbound packets. charon.plugins.socket-default.set_source = yes Set source address on outbound packets, if possible. charon.plugins.socket-default.use_ipv4 = yes Listen on IPv4, if possible. charon.plugins.socket-default.use_ipv6 = yes Listen on IPv6, if possible.